594 inventions: Egypt Ancient African inventors, many of them women, devised methods and devices for gathering, preserving, and preparing food (including the mortar and pestle for grinding and pulverizing foods), herbs, and medicines They created devices for carrying both food and infants (often at the same time), including slings for infants They learned to use sticks as levers for moving rocks, tree stumps, logs, and other objects They created hoes and similar tools for digging plants and, later, for cultivating the earth for planting, and they invented one of the world’s first plowshares (the metal blade of a plow) They learned how to tan and preserve animal hides for use as clothing and blankets, which they sewed with needles made of bone and dyed with natural substances such as henna Later they learned how to weave and spin fabrics They created the first pottery and learned to use kilns to fire the pots, which were then used for food storage or carrying water One important adaptation of fire in ancient Africa took place some 2,000 years ago in the region around Lake Victoria There archaeologists have discovered ancient blast furnaces used in the production of carbon steel (Carbon steel is an alloy of iron and carbon Iron not alloyed with carbon remains relatively soft, but the introduction of carbon hardens the metal.) Carbon was introduced into the iron ore by an ingenious process First a bowl-shaped hole was dug in the ground The hole was then lined with soil taken from a termite mound, and a handle that rose above ground level was inserted so the steel could be removed The chief innovation the Africans introduced to existing furnaces was to insert tubes or blowpipes through the walls of the mound into the pit These tubes channeled air into the fire, creating a blastfurnace effect as the hot air from the fire rose, sucking air through the pipes into the fire Grasses and reeds were then burned in the pit, and when the temperature reached a high enough level, charcoal and iron ore was added The carbon from the burned grasses and charcoal added carbon to the iron, resulting in carbon steel It is estimated that these furnaces could achieve a temperature of nearly 3,300 degrees Fahrenheit Of course, the ability to produce carbon steel presupposes the existence of mining technologies, and the oldest-known iron mine in the world, dating back some 43,000 years, has been found in Swaziland Ancient Africans invented several systems related to calculation The Yoruba tribe had a number system based on 20, and the so-called Ishango bone, dating to 8,000 years ago, has a system of notches that indicates a number system In East Africa accurate calendars were developed in the first millennium b.c.e., and megaliths (vertical stone slabs) enabled ancient Africans to make accurate observations of star constellations Ancient Africans also developed water clocks, an aerodynamic glider, and the game of chess In the area of health care, ancient Africans developed various medicines, including aspirin, a treatment for diarrhea, and a smallpox vaccination remarkably similar to the smallpox vaccine developed by Robert Jenner in the late 18th century Cosmetics invented in ancient Africa included eye shadow to reduce the glare from rivers, similar to the black patches modern-day football player use to reduce glare Other cosmetics were fingernail polish, breath fresheners, wigs, pomades, perfumes, and various dyes to enhance skin color To apply these cosmetics, African women invented the first mirrors, made of polished copper The drum, probably the world’s first musical instrument, was invented in Africa and used on ceremonial occasions and for communication Africans also crafted seaworthy boats, and some archaeological evidence suggests that ancient Africans were able to reach the coasts of the Americas Petroleum, too, was produced around 4000 to 3000 b.c.e To this list must be added the invention of civilization itself, for the Africans were the first to live in human communities that survived, grew, and spread in large part by passing their inventions down to future generations EGYPT BY WILLIAM H PECK The inventions of the ancient Egyptians include ideas and innovations both great and small One important innovation that still affects us today is the observation of the 365day solar year The Egyptians divided the year into 360 days—three seasons of 120 days, 12 months of 30 days—and added five days dedicated to the gods to complete the cycle They also added the rough equivalent of a leap year to make the calendar correspond more closely with their observations of the sun They divided the day into 12 hours of daylight and 12 of darkness, giving us the 24-hour division we also still use The Egyptians produced the first paper, which they manufactured from the papyrus plant, in contrast to the clay tablets used by the ancient Mesopotamians With the introduction of papyrus as a convenient writing surface that was flexible and portable, they also developed the inks necessary for writing Papyrus made possible a giant step forward in the creation and preservation of documents of all kinds With the use of papyrus, one of the most important inventions sometimes credited to the ancient Egyptians was the ability to make meaningful signs that could be understood to record sounds and ideas—a written form of language Historians debate whether the Egyptians or the Sumerians in Mesopotamia came up with the idea first Recent discoveries at Aswan in the south have led some scholars to reassert the idea that writing was first invented in Egypt Not everyone agrees with this In any case, before 3000 b.c.e a method of recording lists of foodstuffs or other objects began to be developed in Egypt As with many other early written languages (such as Sumerian, Chinese, and Mayan), the first stages were essentially pictographs, pictures that stood for things When this method was extended to convey ideas as well as objects, it was necessary to use pictures as phonograms, signs that conveyed